Portion of a shoe sole



FIG. 1 is a plan view of a portion of a shoe sole showing my new design;

FIG. 2 is a front perspective view thereof; and,

FIG. 3 is a rear perspective view thereof.

The uneven broken lines showing the remainder of the shoe sole, and the shoe upper, are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a portion of a shoe sole, as shown and described. 